1. Field of the Invention
The invention relates to the detection and measurement of substances present in a fluid and more particularly relates to those methods and apparatus based upon the light transmissiveness of the fluid.
2. Brief Description of the Prior Art
The prior art literature is replete with descriptions of methods and apparatus for the detection and measurement of substances present in fluids. Representative of descriptions found in the prior art are those found in U.S. Pat. Nos. 3,773,426 and 4,240,751.
In spite of the number of prior art methods and apparatus for detecting and measuring substances present in fluids by determining the light transmissiveness of the fluid, there remains a need for improved apparatus. In particular, there has been a need for highly portable, simple apparatus which can be operated with a minimum of instruction and training.
The assembly of the present invention is compact, simple in design, highly portable and easy to operate. In spite of its simplicity, the assemblies of the invention are accurate and highly reliable in operation.